/*
    Copyright 2009 Christian Henning
    Use, modification and distribution are subject to the Boost Software License,
    Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
    http://www.boost.org/LICENSE_1_0.txt).
*/

/*************************************************************************************************/

#ifndef BOOST_GIL_EXTENSION_IO_BMP_IO_IS_ALLOWED_HPP_INCLUDED
#define BOOST_GIL_EXTENSION_IO_BMP_IO_IS_ALLOWED_HPP_INCLUDED

////////////////////////////////////////////////////////////////////////////////////////
/// \file
/// \brief
/// \author Christian Henning \n
///
/// \date 2008 \n
///
////////////////////////////////////////////////////////////////////////////////////////

namespace boost
{
namespace gil
{
namespace detail
{

template< typename View >
bool is_allowed( const image_read_info< bmp_tag >& info
                 , mpl::true_   // is read_and_no_convert
               )
{
    bmp_bits_per_pixel::type src_bits_per_pixel;

    switch ( info._bits_per_pixel )
    {
    case 1:
    case 4:
    case 8:
    {
        if (  info._header_size == bmp_win32_info_size
                && info._compression != ct_rle8
                && info._compression != ct_rle4
           )
        {
            src_bits_per_pixel = 32;
        }
        else
        {
            src_bits_per_pixel = 24;
        }

        break;
    }

    case 15:
    case 16:
    {
        src_bits_per_pixel = 24;

        break;
    }

    case 24:
    case 32:
    {
        src_bits_per_pixel = info._bits_per_pixel;

        break;
    }
    default:
    {
        io_error( "Pixel size not supported." );
    }
    }

    typedef typename channel_traits< typename element_type< View::value_type >::type >::value_type channel_t;
    bmp_bits_per_pixel::type dst_bits_per_pixel = detail::unsigned_integral_num_bits< channel_t >::value
            * num_channels< View >::value;

    return ( dst_bits_per_pixel == src_bits_per_pixel );
}

template< typename View >
bool is_allowed( const image_read_info< bmp_tag >& info
                 , mpl::false_  // is read_and_convert
               )
{
    return true;
}

} // namespace detail
} // namespace gil
} // namespace boost

#endif // BOOST_GIL_EXTENSION_IO_BMP_IO_IS_ALLOWED_HPP_INCLUDED
